The present invention refers to an assembly device for plate elements such as sheets of paper, cardboard, corrugated cardboard or similar material, for a processing machine.
Generally, the processing machine of plate elements which uses an assembly device is a folder-gluer which comprises a feed station followed by a breaking and prebreaking section for creasing lines of a folding box blank. The breaking and prebreaking section precedes a folding section, which includes a gluing device, followed by an ejection section for the box blanks which have been folded and glued, so as to bring these folded boxes, in a shingle stream, into a delivery station where the are pressed to ensure the glue setting. A folder-gluer is designed for processing box blanks of various sizes between a minimum size and a maximum size. For example, the width of a not yet folded corrugated cardboard box blank can reach up to three meters fifty to obtain a folded box having a width of one meter seventy. Assuming that the section of the mounted box is square-shaped, a parallelepiped box with sides of seventy centimeters would be obtained. For large-sized packaging requiring a quality printing, the size of the printing machines determines the maximum width of the blank. The printing of these blanks is normally carried out on machines allowing a maximum width of about two meters.
The market needs box blanks which are much larger-sized, for example three meters fifty, as mentioned above. In this case, cardboard articles in a plurality of pieces should be used, and these are generally assembled at the time of the packaging. Another solution is to connect two or more cardboard pieces by their lateral edges, so as to obtain a final blank of very large width. Cases can also arise wherein a box must be provided with a reinforcement or protection piece for the product to be packaged. Solutions for connecting two cardboard pieces have already been developed. One solution is described in patent FR 2 816 879 which refers to assembly equipment including a feed station comprising two magazines arranged on both sides of the median axle of the equipment. Each magazine is equipped with a blank picker for feeding two parallel conveyor belts provided with drive pins having to be implanted onto the conveyor belts at intervals corresponding to the dimension of the panels to be conveyed. Therefore, it is necessary to modify the position of the pins at each size change of the panels which are driven by the support of these pins onto their rear edges. This equipment also includes a gluing station of a linking strip of one of the panels as well as a connecting station, of the two panels, comprising two conveyor belts of the two panels and a transverse alignment means. This connecting station includes a rest surface having a ramp for raising the lateral edge of one of the panels and positioning it, in the alignment area, in a plane such that the lower surface of the panel is slightly raised with respect to the upper surface of the other panel which has a glued lateral strip. The transverse alignment is performed by a cylinder, or an equivalent means, which acts on the lateral edge of the panel to be connected to the other panel. Before connecting, a glue strip has been deposited on the linking strip of one of the panels. After connecting the two panels, pressure is exerted, on the two panels at the level of the linking strip.
This kind of equipment enables assembly of two cardboard panels and cannot be used for a different purpose such as inserting a reinforcement piece into a large-sized panel. Inserting is frequently required for increasing the protective effect of the packaging on the product it contains. Such a device for inserting a reinforcement into a box blank is described in detail in Swiss patent CH 575 826.